Introduction 13C‐breath tests are valuable, noninvasive diagnostic tests that can be widely
applied for the assessment of gastroenterological symptoms and diseases. Currently, the …

The carbon isotope values in the exhaled breath of an animal mirror the carbon isotope
values of the metabolic fuels being oxidized. The measurement of stable carbon isotopes in …

Background The breath carbon isotope ratio (CIR) was recently identified as a noninvasive
candidate biomarker of short-term added sugars (AS) intake. Objectives This study aimed to …

Breath and diet samples were collected from 29 taxa of animals at the Zurich and Basel
Zoos to characterize the carbon isotope enrichment between breath and diet. Diet samples …

Starvation is common among wild animal populations, and many individuals experience
repeated bouts of starvation over the course of their lives. Although much information has …

Animals can cope with dehydration in a myriad of ways, both behaviorally and
physiologically. The oxidation of protein produces more metabolic water per kilojoule than …

Almost half a century ago, researchers demonstrated that the ratio of stable carbon isotopes
in exhaled breath of rats and humans could reveal the oxidation of labeled substrates in …

Variation in environmental conditions during larval life stages can shape development
during critical windows and have lasting effects on the adult organism. Changes in larval …

Pythons digesting rodent meals exhibit up to 10-fold increases in their resting metabolic rate
(RMR); this increase in RMR is termed specific dynamic action (SDA). Studies have shown …

During fasting, animals rely on a mixture of fats, carbohydrates, and proteins that are derived
solely from endogenous sources. The relative contributions of these metabolic fuels chiefly …